Electrostatic potential and electric field of three charges

AI Thread Summary
The discussion centers on the role of charge q2 in the context of electrostatic potential and electric fields created by two other charges, q1 and q3. Participants note that q2 does not influence the answers to the posed questions, despite its inclusion in the problem. The small value of q2 suggests it might be intended as a "test charge," but ultimately, it remains irrelevant to the calculations. There are also comments on language translation issues affecting clarity in the discussion. Overall, the consensus is that q2's presence serves to create confusion rather than contribute to the solution.
Ugnius
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Homework Statement
Three point charges, q1=q3=9.5 uC and q2=1.28*10^-18 C are placed as shown in picture
a) How strong in electric field in point (0,0), affected by q1 ir q3 . b)Electric potential in point (0,0) affected by q1 ir q3 charges. Let's say electric potential at infinity is 0.
Relevant Equations
V=kq/r ; E=F/q
1633804692307.png


So I started with b)

1633804818229.png

and it there was no q2 this would seem reasonable
I was wanted to ask , what effect does q2 have on potential of these two charges? Because it has to be given for a reason.
 
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Ugnius said:
I was wanted to ask , what effect does q2 have on potential of these two charges? Because it has to be given for a reason.
q2 does not play a role in answering (a) and (b). Your answer for (b) looks correct.

It does seem a little odd that q2 is given but q2 doesn't affect the answer. The very small value for q2 might indicate that it is to be thought of as a small "test charge". But, still, it is not relevant.

The phrase "affected by q1 ir q3" is also a bit odd. "effected" might be better than "affected". And I don't understand "ir".
 
TSny said:
q2 does not play a role in answering (a) and (b). Your answer for (b) looks correct.

It does seem a little odd that q2 is given but q2 doesn't affect the answer. The very small value for q2 might indicate that it is to be thought of as a small "test charge". But, still, it is not relevant.

The phrase "affected by q1 ir q3" is also a bit odd. "effected" might be better than "affected". And I don't understand "ir".
Yes , sorry , I had to translate statement from my native to English , so I might've done some mistakes. I realized that q2 was just a trick to make us doubt our solutions. I sent it , and it seems to be correct.
 
Ugnius said:
Yes , sorry , I had to translate statement from my native to English , so I might've done some mistakes.
OK. That's no problem.
 
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